Machine for rough-cutting precious stones.



E. CHALLET. MACHINE FOR ROUGH CUTTING.l PRECIOUS STONES,

APLlcATloN FILED Nov.1ov. 1915.

1,261,765., Patented Apr. 9,1918.

3 SHEETS-SHEET l.

0 l(\ z a 17( E. CHALLEI. MACHINE FOR ROUGH CUTTING PRECIOUS STONES.

APPLICATION FILED NOV-10,1915.- l

'Patented Apr. 9,1918.

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m ,[nvenfor: @2M/5 fQW/l E. CHALLET.

MACHINE EoR ROUGH CUTTING PRECIOUS STONES..

APPLICATION FILED NOV. I0. 1915.

Patented Apr. 9, 1918. 3 SHEETS-SHEET 3.

. To all 'whom it may concern:

ETIENNE CHALLET, 0F GENEVA,

swrrzEnLANn, AssIGNon. To L.' New vonk, N. Y. j

MACHINE EOE, 'ROUGH-CUTTING PRECIOUS STONES;

f Specification of Letters Patent. l y

Application filed November 10, 1915. Serial No. 60,693.

Be it known that I, ETIENNE CHAmm'r,

citizen of Switzerland, residing at Geneva,

Switzerland, 80 Rue de Stdlean, have invented certain new and useful Improvements in Machines for Rough-Cutting Precious Stones; andvlf` do hereby declare 'thefollowing to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use-the same, reference being had to the accompanying drawings, and Vto figures of reference marked thereon, which form a part of this specification.

' a [regular form,

Ihe present invention relates-to amachine for rough cutting precious stonesdn as a .preliminary to their subsequentcuttingand polishing. The lapi- 'which operates on end and revolves at a dary tool 1s composed of. a hollow cylinder Vhigh speed. At the 'same time an, oscillating. movement Ais imparted thereto so that the stoneapplied against the annular surface of its extremity produces'a uniform wearing away at such surface.

Referring to the drawings:

Figure 1 is a vertical section of amachine embodying my invention;

Y Fig. 2 is a plan view'thereof; Fig- 3 iS an end view thereof;

.-F ig. 4 is a. sectional view of an oil brakek for'regulatlng the speed of feed of the c'ari riage bearing the lapidary tool;

1 of'a stone;

Y Figs. 6V and spindle mechanism, the spindle being shown allows the cylinder to be presented at varydieV and l Y`gitudinal1y for bringing the annular sur- .Figa 5 is a detail-view showing the machmeas setY for cutting. the girdle orv fillet 7 A are sectionalV views of the the stone carrying dop or block 3, and a hollow lpidarytool 4-mountedo a carriage 5 itself mounted in a rotating table, which ing angles in relation to the axis of the spinatV the same time t be displaced lonface of its extremitv in contact with the very uniforml The machine comprises a frame 1 carryl I mgl rotatmgQsplndle 2servii1g to receive of the' carriage is by stone 6 to be rough cut which has beenV stuck Patented Api-.9, 1ers.

in the' ordinary manner on the point of the dop or block 3.l The cylinder 4 is mounted,

l by means of a plate 4'? on a shaft 7,which carries a pulley 8 serving to'rotate it at a high speed. The bearings of the shaft 7, are provided in the two arms of a fork 9 free to turn around astem 10 ,on thecarriage 5. This arrangement of the lapidary cylinder on a pivoted part permits of the slight oscillating movement being imparted y thereto which is necessary for causing its active annular surface 4' to operate over lts entire width. This voscillation is obtained by vmeans of `a return shaft passing through the 4extremities of the arms ofthe fork' 9 and kof a toothed disk 12 (Figs. l2 and 3) having an eccentric movement and mounted on a trunnion 16 on the carriage 5. The shaft l1 carries a pinion 13 which gears with the eccentric disk 12 and a large toothed wheel lwhich is driven by the pinion 15 on the extremity of the shaft -7. The disk 12 acts 1n the manner of a cam; at each rotation, it

raisesthe fork 9 and the whole of the'mechani'sm connected therewith. The eccentricity of the disk 12 is such that theV range of oscillating movement resulting therefrom 'for the fork 9 corresponds approximately to the width of the annular surface 4 of the lapidary tool. Owing to this arrangement, the wearing away of the surface proceeds y and the formation of stripes is entirely avoided. AThe weight ofthe fork 9 and of the mechanism it carries suiiices to maintain the pinion '13 always in contact with thev eccentric disk 12 if the strappass- -ing over the pulley 8 has a horizontal ,travel A ora slightly"downward4 inclined movement; rotherwise'. the contact must be insured by a spring acting on the fork 9.

' A bell crank lever-17 pivoted at- 18 on vthe l table 19 carrying the carriage 5 controls the advanceof the latter. One arm of this lever bears -with its extremity 20 against the Yplate ofa stem 22 and the other arm carries an adjusting' screw 23 -which bears on the extremity of the shaft 7, under the force of a spring 24 facting upon the bell'crankilever 17. This spring therefore tends to-advance the carriage 5 with all the mechanism it car- -ries to maintain the lapidary cylinder 4 with ioo a light pressure in contact with the stone 6 l to be rough cut.. The rate of advance anoilbrake- Yiw ' controlled by the stem 22, on which the extremity 2O of the lever 17 bears. This brake (Fig. 4) consists in a piston 25, the rate of displacement of which within an oil chamber 26 may be rendered variable by a point'- ed screw 27 enabling the outlet orifice of the oil expelled by the piston when the stem 22 operates, in its descent, on the piston rod 28 to be more or less restricted. The chamber 26 communicates by two orifices 29 and 29 with a passage 30 and the travel of the piston is limited between these two orifices,

- one of which can be throttled by the point of the adjusting screw 27. This arrangement enablesthe oil to pass behind the piston and orifices 31 in the latter allows it to pass back to the front of the piston after each operation. A spring washer 32, applied against the face of the piston 25,

under. the effect ofthe pressure of oil, keeps the orifices 31 closed during the advance of(` the piston and allows the passage of oil through these orifices during the return of the piston. A spiral spring 33 situated in the chamber 26 so that it is compressed by the advance of the piston serves to automatically return it back after each operation. To permit ofthis return, the pressure which is exercised upon the stem` 22 by the angles necessary to grind the surfaces (1,5, c

and d of the stone, which are inclined in relation to its axis (Fig. 8).v

Vhen the axis of the cylinder 4 and that of the dop or block 3 are situated in the same place, only the face e of the stone can be operated ,upon. For' operating upon the i man.

For the grinding of `the zone f, called the filetl of the Istone, the spindle 2 should be other surfaces, it is necessary to turn the table. An index 37 on the latter and a scale 38 on the frame facilitates the adjustment of the table to the different angles predetermined by the form of the stones by the worksetradially in relationto the axis of the lapldary cylinder. For this operation use made of a machine identical to that here- ,lnbefore described but in which the spindle Y. k2 whichreceives the stone carrying dop or block is arranged vertically so. as not to interfere with the advance vof Vthe cylinder (Fig. 5).

The dop or block 3 may be screwed on the spindle 2 (Fig. 1). For mounting and removing it, it should be turned away from the cylinder 4. To allow of this movement, thespindle 2 and its pulley 2 are mounted in a frame 39 pivoted on two trunnions 40 provided in a forked portion of the frame 1. `In the operative position, the frame 39 is held against a screw stop 41 by a spring 42 and to move it to the position to allow of the changing of the dop or block, it suliices to lower the lever 43.

This oscillation may be utilized to automatically release the dop or block 3. According to Figs. 6 and 7 'which illustrate a similar arrangement, the dop or block 3 is formed with a heel piece 3 by. which it is retained inthe spindle y2, by means of a spring stem 44 carrying a hook 45 which is also spring actuated. This hook seizes the dopor block by its heel 3, whereas the spring 46 by exercising a pull on the stem 44, in one with the hook 45, holds the dop or block against the conical entrance 47 of the spindle with a pressure sufficient to insure the operation of the dop or block. The hook 45 is pivoted in a slot which is situated in the fore part of the stem 44; it is provided with a small finger 48 which extends into an opening 49 in the spindle 2,. This opening is situated so that the finger 48 abuts against its wall when the stem 44 is forced homel within the spindle and that a pivoting of the hook 45 ensues which liberates the dop or block 3. A bell crank lever 50 pivoted on a pin solid with the frame 39 is arranged in such a way thatit may serve to force home the stem 44 within the spindle and, so that the operation may take place automatically when the spindle is pivoted, an abutment 51 is provided on the frame against which the lever 50 is arrested, which compels this leverto turn and produces the forcing home of the stem 44 within the spindle 2. It is in this position represented in Fig. 7 that the changing of the stone.

carrying dop or block is effected.

The machine hereinbefore described is especially useful for the rough cutting of artificial stones of oXid of alumina for it enables 'them to be rough cut in series and Ythe duration of the operations .to be varied 4for said holder, means whereby said support may be continuouslyA rotated, a carriage adapted to have movement toward and from said holder, a rotatable lapidary wheel mounted upon said carriage, a plvotal supor imitation stones embodying therein a holder for the stones, a carriage adapted to have movement toward and from said holder,

a rotatablelapidary wheel mounted uponsaid carriage, a pivotal support for said carriage whereby the work face ot said lapidary wheel may be set at any desire normally exerting pressure upon said carriage to yieldingly thrust it toward said holder and means regulating the thrust of said means.

v3.- A machine for rough cutting precious.

stones having a hollow cylindrical grinding tool working endwise, means to impart a slight oscillating movement to the said grinding tool, a sliding carriage supporting the' latter, and an oil brake to regulate the advance of said carriage. Y

' 4. A machine for rough cutting precious or imitation stones embodying therein a .holder for the stones, a carriage adapted to have movement toward and from said holder, a rotatable lapidary wheel mounted upon said carriage, a pivotal support for 'said carriage whereby the work :tace of said lapidar'y wheel may be set at any desired angle to the axle of said holder spring actuated means normally exerting pressure upon said carriage to yieldingly thrust it toward said holder and means regulating the thrust of said means comprising an oil chamber, means forming 'a passage adjacent Asaid, chamber, said chamber and said passage bei ing in communication on different levels, a

i .in said chamber,

piston having a port therethrough, mounted a check valve controlling said .port mounted on the bottom of said piston whereby movement of said piston in one direction is possible only with the displacement of oil in said chamber and delivery vthrough said passage to'v above said piston, a

spring-acting uponsaid piston to force it outwardly of said chamber and operative connections between said piston and said spring actuated means.l

w 5. A' machine for lrough or imitation stones embodying therein a .holder for the stones, a carriage adapted to have movement toward and from said holder., a /rotatable lapidary wheel mounted upon said carriage, a pivotal support for said carriage whereby the work face of said lapi2 dary wheel may be set at any desired angle tothe axis of said holder, a bell crank lever, one arm of which is adapted to act upon said carriage and the other armof which is adapted lto be acted upon by a a:brake mechad angle to the axis of said holder, spring actuated means.

- said chamber,

' lated, and a piston stem cutting precious nism, a spring acting upon said 'lever and normally exerting a thrust thereon adapted to yieldingly force said carriage toward said holder for the stones, and a brake mechanism comprising an forming a passage adjacent said chamber, said chamber and said passage being in communication on different levels, a piston having a port therethrough mounted in said chamber, a check valve controlling said port mounted on the bottom of said piston wheremovement 'of said piston in one direction is possible only with the displacement of oil insaidchamber and delivery through said passage to above .said piston, a spring acting upon said piston to force it outwardly .of

ioW of oil from said chamber maybe reguadapted to operatively engage one arm of said bell crank lever.

6. A machine for rough cutting precious or imitation stones .embodying therein a holder for thestones, a carriage adapted to have movement toward and from said holder, a rotatable lapidary Wheel mounted upon saidv carriage, a pivotal support for said carriage whereby the work face of' said lapidary wheeLmay be set at any desired angle to the axis of said'holder, light yielding contact of the lapidary wheel and the stone being out is maintained and oilchamber, meansv means whereby the rate of*v means whereby a means imparting voscillatory movement to said lapidary wheel.

7.. A machine for rough cutting precious or imitation stones lembodying therein a holder ftor the stones, a ca have movement toward and Jfrom said holder, embodying therein a pivotal member. movable about an axis extending longitudinally ofl said carriage, a shaft mounted in said member, means whereby said shaft Amay be stones, a shaft mounted upon said carriage,

a cam upon 'said last named ,shaft engaging holder, and incanswhereby light yielding.

contact of the lapidary wheel land the stone being cut is maintained.`

A 8. A machine for rough cutting precious` .or

Imitation ,stones embodying-.therein a rriage adapted to ioo "rotated, a lapidary wheel mounted upon the end of said shaft toward lsaid holder for the'Y holder Ifor the stones, comprising .a pivotal A frame, a spindle rotatably mounted'k/in said frame, a.l spring acting upon said'lrame', a

stop limiting the operative effect of said spring upon said frame, and-means carried by said spindle whereby a dop or block'lmay l to rotate vwith said spindle, a

carriage adapted to have movement toward`4 ay rotatable 'lapidary be mounted and `from said holder, Y wheel mounted upon said can'age, a. pivotal iso support for said carriage whereby the work face of said lapidary Wheel may be set at any desired angle to the axis of said holder, and means whereby light yielding contact of the lapidary wheel and the stone being cut is maintained.

9. A machine for rough cutting precious or imitation stones embodying thereinA a holder for the stones, comprising a pivotal frame, a spindle rotatably mounted in said frame, a' spring acting upon said frame, a 'stop limiting the operative effect of said spring upon said frame, and means carried by said spindle whereby a dop or block may be mounted to rotate with said spindle, said last named means consisting of a stem slidably mounted in said spindle, a springactuated hook carried by said stem, a spring acting upon said stem, a stud carried by said hook, said spindle having a Way therein in which said stud is seated'and of a length to cause the engagement of said stud With said spindle to oscillate said hook to release the memes the dop or block, a carriageadapted to v have movement toward ,and from said holder, a rotatable lapidary wheel mounted upon said carriage a pivotal support for said carriage whereby the Work face of said lapidary Wheel may be set at any desired angle to the axis of said holder, and means Whereby light yielding` contact of the lapidary wheel and the stone being cut is maintained. In testimony that I claim the foregoing I have hereunto set my hand this sixteenth day of September, 1915.;

, v ETIENNE CHALLET.

Witnesses:

H. W. FRIEDLA'ND, R. SOLLBERGER. 

